Manufacture of a leno interlacing



Feb. 3, 1970 FjLU-rz 3,493,013

MANUFACTURE OF A LENG INTERLACING Filed March ll, 1968 8 Sheets-Sheet 2 Fel.4 3, 1970 num 3,493,013

MANUFACTURE OF A LENG INTERLACING Filed March 11, 1968 8 Sheets-Sheet 5 se 56 5l. 52v

Fig.5o lo so sa 56 54 F. LUTZ MANUFACTURE OF A LENO INTERLACING Feb. 3, 1.970

8 Sheets-Sheet 4 Filed March ll. 1968 Feb. 3, 1970 F. LUTZ MANUFACTUHE 0F A LENO INTERLACING Filed March l1. 1968 Feb. 3, -1970 F. LuTz MANUFACTURE OF' A [.ENO INTEHLACING 8 Sheets-Sheet 8 Filed March 1l. 1968 United States Patent O 3,493,013 MANUFACTURE OF A LENO` INTERLACING Friedrich Lutz, Durnten, Switzerland, assignor to Ruti Machinery Works Ltd., Ruti, Zurich, Switzerland, a corporation of Switzerland Filed Mar. 11, 1968, Ser. No. 712,177 Claims priority, application Switzerland, Mar. 10, 1967, 3,497/ 67 Int. Cl. D03c 11/00; D03d 25 00, 23/ 00 U.S. Cl. 139-54 14 Claims ABSTRACT OF THE DISCLOSURE An `arrangement for the manufacture of a leno interlacing having a leno thread wrapped around a predetermined number of warp threads which includes iirst and second thread guide means, each reciprocal in a direction of movement of the healds on a loom for actuating a leno thread. The first thread guide means is disposed on one side of the predetermined number of warp threads and the second thread guide means is disposed on the other side of the warp threads. Two entrainment means are arranged on the second thread guide means so that during the reciprocal movement of this means, one entrainment means entrains the leno thread in the one direction of movement and the other entrains the leno thread in the other direction of movement. An intermediate space is also provided between the two entrainment means wherein the leno thread is freed from the entrainment means. A method of forming the leno interlacing and the resulting leno interlacing are also disclosed.

The present invention relates to a method for the manufacture of a leno interlacing or pattern in which by actuating a crossing or leno thread in the direction parallel to the direction of movement of the heald shafts of a loom a predetermined number of warp threads have a leno thread wrapped about them, the arrangement or apparatus for carrying out the method and the leno interlacing made thereby.

Various types of arrangements for the manufacture of leno weaves are known. These generally have healds which move parallel to their longitudinal direction and with the aid of which crossing threads are displaced in accordance with a program. It is also already known, for the manufacture of selvedges,.to draw off two crossing threads from continuously rotating yarn bobbins and to entwine the crossing threads with each other while simultaneously inserting weft threads between them.

Attempts are continually being made to improve such leno weaves. In particular, the weaves are to be of such a nature that no slipping takes place between the threads which have been intertwined with each other, i.e., the threads are retained in their mutual position in such manner as to be non-displaceable to the maxium extent. This is of decisive importance particularly when the leno interlacing is used for a selvedge.

Advantageously the present invention makes possible the manufacture of an extremely strong and firm leno interlacing which is suitable both for leno fabrics, for outer selvedges and also for between-selvedges.

Thus this invention, contemplates a method of producing a leno interlacing as heretofore described further characterized in that the leno thread is selectively moved to and fro both on one side of the predetermined number of warp threads and also on the other side of the predetermined number of warp threads, and the leno thread is permanently retained on said one side and, on said other side, selectively retained or released.

This invention furthermore is directed to an arrange ment or apparatus for the manufacture of leno inter lacing by which a predetermined number of warp thread are embraced by a leno thread, the arrangement com prising a first and second yarn or thread guide mean: adapted to be reciprocated in the direction of movemen of the healds for actuating the leno thread, said iirs thread guide means being disposed on one side of tht predetermined number of warp threads and the secon( thread guide means being disposed on the other sidt of the said predetermined number of warp threads said second thread guide means having two entrainmen means whereby during the reciprocating movement o1 said second thread guide means one of said entrainmen` means entrains the leno thread in the one direction oi said movement and the other entrains the leno threac in the other direction of said movement, said seconcl thread guide means also having between the two entrainment means an intermediate space in which the lenc thread is free from the entrainment means and which is open in the direction towards the predetermined number of warp threads.

In addition, this invention is concerned with a lenc interlacing wherein a predetermined number of warp threads are embraced by a leno thread characterized in that the leno thread lies, in the form of a U-shaped loop, alternatingly over the predetermined number of warp threads and below the predetermined number of warp threads, the curved portion of the loops extending over the warp threads and also of the loops extending under the warp threads, being wound about a weft thread and the wound-around portions of the U-shaped loops wrapped about the weft threads being located on the same side of the leno interlacing.

Due to the provision of two yarn or thread guide means of the type heretofore described, it becomes possible to lay the crossing thread selectively in the one or in an opposite direction about the warp threads which are to be embraced or to travel through with the leno threads alternatingly under and over the warp threads. lt is possible to completely wrap around the warp threads, a weft thread being inserted after each such wrappingaround. Thus, with the arrangement according to the present invention, it becomes possible to produce a very large variety of leno interlacing.

At the same time, the arrangement has only rectilinearly displaced parts, which may consist of thin strips, tapes or finished healds. Thus, the larrangement according to the invention is simple and a strong construction, and may be designed to be extremely narrow in the weft or pick direction. In this way, spreading-apart of the warp threads (which might possibly result in marking of the fabric, i.e., in weaving flaws) is practically avoided. Furthermore, when the arrangement according to the invention is employed, any possibility of hindering of the warp threads during shedding is quite readily avoided.

The invention will now be described in greater detail with reference to the embodiments shown in the drawings in which:

FIGURES 1, 2, 3, 3a, 4, 4a, 5, 5a, 6, 6a, 7, `7a, 8 and 8a show, in diagrammatic form, an embodiment of the arrangement or apparatus of the invention, its mode of operation and the leno interlacing made thereby;

FIGURES 9, 9a, 10 and 10a show two variants of the embodiment shown in FIGURE 1 and the leno interlacing made thereby;

FIGURES 11 and 11a show a further embodiment of the arrangement of the invention in a lateral elevation and the leno interlacing made thereby;

FIGURES 12, 13a, 13b, 14a, 14h, 15a, 15b and 16 3 ,her illustrate the mode of operation of the embodiit shown in FIGURE 11; "IGURE 17 shows, in diagrammatic form, an embodint of a drive for the predetermined number of warp :ads and the crossing thread. n all the figures, like reference numerals designate like nents. iIGURE 1 shows an arrangement or apparatus for the nufacture of a leno fabric or a leno selvedge in eleva- 1 and FIGURE 2 shows a plan view of the same ar- .gement. The two healds 31 and 32 are moved individur, but may also be associated with the standard shafts the weaving machine. The healds move the warp eads 33 or 34, respectively. A crossing or leno thread is guided through the eyelet 35 of the yarn guide 36 hich comprises a first yarn guide means). The threads end from the above-described elements 31, 32 and 36 ough a slot arrangement or means, comprising the iight slotted portions 38, 38 and the ends 44, 45, to 1 fabric 40. In order to indicate that the arrangement lstrated serves for the formation of a lateral selvedge, iitional warp threads 41 and 42 are only shown in SURE 2. These threads represent the end of the shed. e slots forming the portions 38 and 38 are formed by lngated plates or thread guiding means 43 and 43. ch slot comprises a rectilinear portion 38 (or 38') and curved ends 44 and 45.

On a weaving loom, the fabric is normally at the for- `rd part of the machine. Thus, in the drawings, in the rmal direction of viewing the loom, the fabric 40 de- `mines the position of the forward part of the loom. iwever, when describing the present invention, it is to assumed that forward and behind are dened in ation to the views of the gures showing lateral elevans, so as to simplify the mode of expression used in the scription.

The leno thread 37 travels from a leno thread supply ot shown) on the forward side of the first yarn guide guide means 36 (i.e., in front of the guide as shown FIGURE 2) through the eyelet 35, behind the yarn ,ide 36 and in front of the plate 43, through the curved .d 44 of the slot, through the plates 43, 43 and from ate 43 to the fabric 40. The warp thread 34 extends rough the eyelet of the heald 32, through the slot por- )ns 38, 38 and from the latter, behind the plates 43 and i', to the fabric 40. The warp thread 33 travels through e eye of the heald 31 arranged behind the heald 32 rd also through the slot portions 38, 38 and from the tter, behind the plates 43, 43 to the fabric 40.

The plates 43, 43 are secured, by means of screws, ith the loom. Arranged between the plates 43, 43 is second yarn guide or guide means 46. Both the yarn ride 36 and also the yarn guide 46 are movable parallel the direction of movement of the shafts of the loom, e. parallel to the rectilinear portion 38 of the slot in .ate 43. The second yarn guide 46 is designed as a rod r tape and is formed with entrainment means i.e., in- :ntations 47 and 48 extending in its longitudinal direcon. The indentations serve to entrain the leno thread 37. etween the indentations is an intermediate space ex- :nding between the limiting portions or projections 49 nd 50. As can readily be seen in FIGURE 2, the interiediate space is open towards the righthand side and )wards the warp threads 33 and 34.

A thread disposed in the curved end 44, such as for exmple the thread 37 is, as the yarn guide 46 moves downyardly, entrained by the indentation or by the entrainlent means 47. Similarly, if the yarn guide 46 is in its )wer position, coinciding with the curved end 45, a thread isposed in the end 45 is entrained by the indentation or y the entrainment means 48. If, on the other hand, a iread is disposed inthe rectilinear portion 318 of the slot 1 plate 43, then it will not be engaged by the said entrain- :tent means 47 or 48. The slot arrangement or means 38,

44, 45 in plate 43 thus serves as a guide arrangement for the leno thread 37, in as much as, with the aid thereof, the threads are guided into the indentations 47, 48 an-d out thereof.

The yarn guides 36 and 46 are individually driven. Their movement development depends on the nature of the leno interlacing to be manufactured. FIGURES 1 and 2 also show the weft threads 51, 52, 53, 54, 55, 56 and 57 of the fabric 40.

In explanation of the mode of operation of the arrangement or apparatus during the manufacture of a leno interlacing, FIGURES 3 to 8 show various, successive positions of the healds 31 and 32, the yarn guides 36, 46, the warp threads 33, 34 and the leno thread 37 In FIGURES 3 to 8, no plan View, corresponding to FIGURE 2, has been shown. However, the elevation of the fabric 40 or 40 has been included in each of the FIGURES 3cr-lla as a fragmentary plan view.

For the further development of the leno interlacing extending in FIGURE 1 over the weft threads 51 to 56, the closure of the open-shed position of the warp threads 33, 34 (as shown in FIGURE l) is commenced. While these threads travel in the rectilinear portion 38 of the slot in plate 43, the yarn guide 46 is displaced downwardly. As this takes place, the indentation or the entrainment means `47 engages the crossing thread 37 whereby the thread is drawn, from its position above the warp threads 33, 34, behind them and downwardly. This movement can be most clearly seen from FIGURE 2.

The warp threads 33, 34 extend to the right of the yarn guide 46 (see also FIGURE 3) and are not engaged by guide 46, but the leno thread 37 is retained thereby with the indentation 47. Therefore, the thread 37 must, if it is drawn downwardly, along the inner, left-hand edge of the slot portion 38 against which it bears, slip through ybetween the latter and the warp threads 33, 34. It should be noted that, as this takes place, the yarn guide 36 (and with it the eyelet 35 thereof) remains stationary. Similarly, thread 37 must slide, at the inner, right-hand edge of the slot 38 about which it bends round, downwardly over the threads 33, 34. An intermediate position of this movement is shown in FIGURE 3. Before the warp threads 33, 34 have passed through their closed shed position, the weft thread 57 has been beaten up. The plan view of the fabric 40 shows how, from the above discussed procedure, the leno thread 37 has been laid over the two warp threads 33, 34.

After the downward movement of the yarn guide 46 and the shed-change in respect of the warp threads 33, 34 has been effected, a new weft thread 58 is picked-in. This condition is shown in FIGURE 4. As the nextfollowing movement, the shed formed by the warp threads 33, 34 begins to close once more and the weft thread 58 is beaten up. When the warp threads 33, 34 are again in the rectilinear portion 38 of the slot, the yarn guide 46 again commences its upward movement.

The end position of the movement of guide 46 is shown in FIGURE 5. In this working phase, a weft thread (i.e., the weft thread 59) is again picked. Thereupon, the shed formed by the warp threads 33, 34 is changed and the weft thread 59 is beaten up. Simultaneously with the shedchange, the forward yarn guide 36 moves downwardly. Since the yarn guide 46 remains stationary at the commencement of this movement, the leno thread 37 is, due to the downward movement of the yarn guide 36, displaced along the curved end 44 and, as it turns into the rectilinear portion 38 of the slot in plate 43, leaves the intermediate space lbetween the projections 49 and 50. In this way, the leno thread 37 (as will be more readily comprehended from FIGURE 2) is rst of all drawn at the forward, left-hand, inner edge of the slot in plate 43 forwardly over the warp threads 33, 34. At the same time, it slides along these warp threads 33, 34, down over them at the forward side. Correspondingly, it slips at the inner, right-hand edge of the slot portion 38 between the right-hand edge and the warp threads 33, 34. After the yarn guide 36 has commenced its downward movement, and in particular after the leno thread 37 has taken up its position in the rectilinear portion 38 of the slot, the yarn guide 46 is displaced downwardly in an idle movement. The weft yarn 60 is also inserted.

The end position resulting therefrom is shown in FIG- URE 6. The corresponding plan view of the fabric 40, illustrated in FIGURE 6a, also shows how the leno thread 37 is wound round the weft thread 58, forming a U-shaped loop lying over the warp threads 33, 34. At the next movement during the further production of the leno interlacing 40, the shed formed by the warp threads 33, 34 (shown in FIGURE 6) begins to close. Then the yarn guide 46 is moved upwardly. During this movement, the indentation or the entrainment means 48 engages the leno thread 37 and displaces it upwardly. Consequently, the leno thread 37 on the rear side of the warp threads 33, 34, and first at the position of the slot 38 (see FIGURE 2) behind the warp threads 33, 34 is drawn over the threads, upwardly: this movement being propagated upwardly and rearwardly over the warp threads from the slot 38', towards the right and towards the fabric. Correspondingly, the leno thread 37 is, at the inner, left-hand edge of the slot 38 against which it bears, drawn through between the edge and the warp threads 33, 34.

The new condition resulting therefrom is shown in FIGURE 7. In this figure, the new weft thread 61 which has been picked is also shown. As can be seen from the plan view of the fabric in FIGURE 7a (and as a result of the condition just described) the leno thread 37 has been drawn through under the warp threads 33, 34 and the weft thread 60. With the beating-up of the weft thread 61, there again takes place the closing of the shed and, with an appropriate delay, a movement of the yarn guide 46 in the downward direction. The weft thread 62 is then picked.

This movement results in the condition shown in FIG- URE 8. As the next step for the further formation of the leno interlacing, the shed change in respect of warp threads 33, 34 recommences. Simultaneously, the forward yarn guide 36 travels upwardly. During this movement, the leno thread 37 travels out of the intermediate space located between the projections 49 and 50 and along the curved end 45 towards the rectilinear portion 38 of the slot. During a further part of this movement, the leno thread 37 is displaced by the yarn guide 36, at the inner edge of the slot 38 against which it bears, forwardly over the Warp threads 33, 34. Then, the thread 37 is drawn upwardly also at the inner edge of the slot 38', against which it lbears, between the edge and the warp threads 33, 34.` Additionally, the yarn guide 46 also travels upwardly in an idle stroke and with a corresponding delay. In the end position resulting from this movement, both the yarn guide 36 and also the yarn guide 46 are again in their upper end positions. The warp thread 33 is again in its Alower shed position and the warp thread 34 in its upper shed position. These end positions correspond exactly to the positions of the elements shown in FIGURE 1. Naturally, as compared with FIGURE l, a complete repeat (or cycle of leno interlacing) has been further added.

From the plan view of the fabric shown in FIGURE 8a it will be apparent that, as a result of the procedure described with reference to FIGURES 6 to 8, the leno thread 37 is wrapped about the weft thread 61 and forms a U-shaped loop extending under the warp threads 33, 34.

FIGURE 9 shows a form of embodiment which has been varied relative to the embodiment heretofore described. The difference between the embodiments is that the second yarn guide means comprises a guide 46a with an intermediate zone between the entrainment elements 47 and 48 or between the projections 49 and 5 designed to be somewhat longer than the length of th slot made up of portions 38, 44, 45. The advantage of thi embodiment will be appreciated if the mode of operatio: described with reference to the embodiment illustrated b1 FIGURES 1 to 8 is recalled. In that case, after the down ward movement of the yarn guide 36, a downward idlin, movement of the yarn guide 46 took place, thus pro ducing the condition shown in FIGURE 6. In an anal ogous manner, after the condition shown in FIGURI 8, an upward movement of the yarn guide 36 takes plac and this is followed by an idling movement of the yarl guide 46 in the upward direction: consequently, the con dition shown in FIGURE 1 is again attained. In the ar rangement shown in FIGURE 9, the two idling move ments just described are no longer necessary.

Also the embodiment shown in FIGURE 10 serves, a: compared with the form of embodiment rst described to simplify the upward and downward movement of the second guide means. The description in the foregoing tex' pointed out that the yarn guide 46 is intended to carry out its movement, after the commencement of the shec` movement, effected by the healds 31, 32. The reason fol this step resides in the fact that undesirable entrainment of threads disposed in the slot ends 44, 45 is to be avoided, since threads disposed in the curved slot ends 44 and 45 are entrained by the entrainment elements or means 47 or 48. The embodiment shown in FIGURE l0 has the advantage that the shed movement in respect of the threads 33, 34 is able to commence simultaneously with the movement of the yarn guide 46, because of the increased length of slot 38, 44, 45. The yarn guide 36 must, also in this case, move in every instance before the yarn guide 46, in order that the guide 46 may not be able to engage the, leno thread 37 during its idling movement.

In yet a further embodiment which, however, is not shown, the end position of one of the entrainment means 47 is above the curved slot end 44 and the end position of the further entrainment means 48 is below the curved end 45, in the case of a design of the slot 38, 44, 45 as shown in FIGURE l0. This embodiment is thus a combination of the examples shown in FIGURES 9 and l0. It has the advantages mentioned in connection with those gures. In this case, wherein the idle movement of the yarn guide 46 is again dispensed with, also the forwardshifting of the movement of the yarn guide 36 is no longer necessary.

FIGURE ll shows a further embodiment of the invention. According to this embodiment, the shed-formation in respect of the warp threads 33, 34 is effected once again by healds 31, 32 and the leno thread 37 is again displaced by an eyelet 35 in the first yarn guide means comprising a yarn guide 36. The FIGURES ll and lla show additionally the leno interlacing or pattern 40' formed from the warp threads 33, 34, the weft threads 61, 62, 63 and the crossing thread 37. In this embodiment, the leno interlacing comprises two warp threads 34 and, associated therewith, two healds 32.

The second yarn guide means includes a yam guide 46', having a shape devating from that described in the preceding embodiments. This can be seen most clearly from FIGURE l2, which illustrates the arrangement of FIGURE ll in section, as seen from the left-hand side of FIGURE ll. The yarn guide 46 is provided with two entrainment means or indentations 67 and 68 for the entrainment of the leno thread 37 downwardly or upwardly respectively. According to this embodiment, the ends 44, 45 of the slot having portion 38 are not necessary for displacing the crossing thread 37 in the zone of the entrainment means 47, 48, since the eyelet 35' is so shaped that it retains the thread 37 permanently in the zone thereof. The thread 37 travels from a supply bobbin (not shown) through the eyelet 35' and downwardly,

n over the indentation 67 and then to the leno intering 40', i.e., towards the right in FIGURE 11 and, in SURE 12, away from the viewer.

FIGURES 12, 13a, 13b, 14a, 14b, 15a, 15b and 16 )w various phases of the movement of the yarn guides and 46. In order to make the arrangement clearer, GURES 13a to 15a show the end elevations and FIG- {ES 13b to 15b show the corresponding plan views (as 'fwed from the left hand side of FIGURE 11). As can seen from the figures, there has been provided for a guiding of the warp threads 33 and 34 associated with s leno interlacing 40', a yarn guiding means 65 which s the form of an elongated rod. The function thereof nsists substantially in pressing the warp threads 33, 34 t of the travel path of the yarn guide 46'.

In explanation of the mode of operation of this arugernent, it will be assumed that it is in the condition work phase shown in FIGURE 1l. This corresponds that shown in FIGURE 12. During the further forma- )n of the leno interlacing the weft thread 64 is rst aten up and the shed formed by the warp threads i, 34 is closed, as shown in FIGURE 13a. Simultanelsly, the yarn guide 36 travels downwardly and the .rn guide 46 travels upwardly towards its center posim. In this way, the thread 37 passes into a position herein it is free from the two entrainment means 67, 68 the yarn guide 46 and travels therein from the inner :le of the leno interlacing (the side of points A, C shown the fragmentary plan view of FIGURE l1) to the aperre in the eyelet 35 located at the side of the yarn guide i. Since this aperture extends more towards the side E the yarn guide 46 than the warp threads 33, 34, the no thread 37 does not cross the warp threads and avels obliquely upwardly to the position of the leno iterlacing as shown in FIGURE 13a.

In the case of the movement development shown in IGURES 13a, 14a and 15a the eyelet 35 is then disiaced on the right of or outwardly past the warp threads 5, 34. These warp threads are pressed somewhat towards te left, during the travel-through of the guide 36 carrylg the eyelet 35 due to the wedge-shape or tapered shape E the eyelet. During this procedure, the leno thread 37 t naturally entrained by the eyelet 35, i.e., it is laid over nd around the warp threads 33, 34. This step terminates t the phase shown in FIGURES 14a and 15b.

After the eyelet 35 has travelled past the Warp threads 3, 34, the threads are again displaced out of the entrainient zone of the indentations `67 and `68. As already stated, 1 is the purpose of the guide strip or rod 65 to press the larp threads 33, 34 out of the entrainment zone of the ndentations 67 and 68. Due to the procedure hitherto decribed, the crossing thread 37 now extends from a point n the inner edge of the leno interlacing over the warp hreads 33, 34 and then, extending downwardly somevhat, to the eyelet 35'.

In the next working phase, the leno thread 37 is before he yarn guide 36 has travelled completely downwardly, ngaged by the entrainment means 68 and drawn upvardly, as shown in FIGURE 161. In this way it is still urther tiwsted or wound about the warp threads 33, 34. 'n order to be able to follow the entire procedure with leference to the plan view of the leno pattern 60 shown n FIGURE 11a, it should be pointed out that, during he formation of the leno pattern, the same procedure is 'epeated after each two successive weft threads. Thus, it nay be assumed that, previously, instead of the weft hread 64, the weft thread 62 was picked. Consequently,

luring the step shown in FIGURES 13a to 15b, the crosslng thread 37 has been laid from point A over the warp breads 33, 34, to point B. Due to the entrainment of the :hread 37 by the indentation 68, in the manner shown in FIGURE 16, it travels from the right-hand side of the leno pattern through, under the Warp threads 33 and 34 and is drawn upwardly on the left-hand side of the Warp 8 threads. In this way, thread 37 passes into the position C.

Simultaneously, opening of the shed takes place and a new weft thread is inserted. With the assumption made hereinabove, this will be considered to be the weft thread 63. If attention is given to the leno pattern 40 shown in FIGURE 1l, it will now quite readily be appreciated that, as the next movement step, the yarn guide 46' will move downwardly into its middle position and the shed of the warp threads 33, 34 will close again, accompanied :by the beating up of the weft thread 63. Thereby, theleno thread 37 extends obliquely downwardly from the interior of the leno pattern (position C). Simultaneously, the yarn guide 36 is displaced upwardly. As this takes place, and after the leno thread 37 has been freed from the indentation 68, the thread 37 rst of allextends fromrpoint C obliquely downwardly to the eyelet 35. Since the eyelet 35 has the wedge shape which projects towards the yarn guide 46 in this working phase, the leno thread 37 does not yet cross the warp threads 33, 34. Thereupon, the yarn guide 36 moves further upwardly and displaees the eyelet 3S' on the right past the warp threads 33, 34 which are in 'the shed-closed position. During this procedure, the leno thread 37 is laid-through under the warp threads 33, 34 and extends through the position D from which it now extends obliquely upwardly to the eyelet 3S.

During the further development of the movement of the yarn guides 36', 46 the yarn guide 46' travels further downwardly. The warp threads 33, 34 are, during this step, again located externally of the entrainment zone of the entrainment means 67, 68. The leno thread 37 which, however, is positioned within Ithis entrainment zone is engaged by the entrainment means 67 and drawn downwardly. Thread 37 thereby takes up its position obliquely over the warp threads 33, 34 and extends at the end of this movement phase from the outer edge of the leno interlacing (position D) over the warp threads 33, 34 and obliquely downwardly to the entrainment means -67 of the yarn guide 46 which is now in its lower end position. The yarn guide 36 has meanwhile reached its upper end position and a new weft thread 64 may be picked-in. This terminates a complete period of the leno interlacing and the mode of operation again commences from the beginning of the work cycle.

Both the fabric interlacing manufactured with the arrangement of FIGURES 1 through 8 and also thatmanufactured with the arrangement of FIGURES 11 through 16 are distinguished for their stability. It is characteristic of both fabric interlacings that they travel-throug alternatingly above and belowthe warp and weft threads. Thissymmetry results in good cohesion of the interlaclng, Le., in a high degree of durability. When the interlacing is used as a selvedge, it is especially advantageous that the looped-around portions of the leno thread wrappedabout the weft threads are all on the same side. In order to fo-rm an-edge of maximum firmness, these wrapped-around portions are provided on the inner side of the selvedge, i.e., at that yside of the selvedge adjacent the fabric. If the wrapped-around portions were to be disposed on the outer side ofl the selvedge, then they might slip oitr from the weft yarn ends, when these ends sag.

The edge of interlacing produced by 'the vembodiment of the apparatus iirst described is less dense than the edge of that produced in the last described embodiment. However, it will be quite clear to the person skilled in the art that this does not result from the arrangements or apparatus disclosed per se but from the mode of actuating the same. If, in the embodiment lirst described, during a full cycle of movement of the leno.thread,-only a part of the weft lthreads were to be picked, as in the case in the description, i.e. if, for example, the weft threads 51, 53, 54, 56, 57, etc. were not to vbe inserted, then `the fabric interlacing according to the embodiment last described would be obtained. It will thus be clear that, with the arrangements illustrated, not only may the two leno patterns illustrated with the embodiments be produced but also a large number of varying leno pattems.

In FIGURE 17, there is shown in diagrammatic form an embodiment of a device or means for producing the movement of the predetermined number of warp threads 33, 34 and of the yarn guides 36, 46 for actuating the leno thread 37. The warp threads 33, 34 are, as already described, displaced by means of the healds 31, 32. The leno thread 37 again travels through the eyelet 35 and the slot 38, 44, 45 formed in the plate 43. The plate 43 is, through the agency of the carrier or support 99 secured to the loom frame 98.

The healds 31, 32 and the yarn guides 36, 46 are continuously subjected, by the tension springs 70, 71, 72, 73, to an upwardly directed traction force. At their lower ends, they are, as shown in FIGURE 17, secured to the levers 74, 75, 76 and 77 respectively. The levers are pivotal about the xed pivot 96. Each of the levers 74, 75, 76, 77 .carries a roller (of these only rollers 78, 79 and 80 are visible). Due to the pull of the springs 70 to 73, the levers 74 to 77 also are subjected to a continuous upward pull. In this way, each roller' is pressed against a guide cam pivotal about the pivot 81. With this arrangement, the following elements are operatively associated with each other:

v The roller 78 of the lever 74 and the guide cam 82; The roller 79 of the lever 75 and the guide cam 83; The roller 80 of the lever 77 and the guide cam 85. The roller of the lever 76 (connected to yarn guide 36) is disposed behind the roller 79 and is moved by the guide cam 84. In order to show clearly the path followed by the guide cams, the reference numerals designating the cams are, in part, shown at various positions of the cams.

The regulating roll 86, over which the warp threads 33, 34 are guided, is movable perpendicularly to the longitudinal direction thereof, in order that the warp threads may, during the shed movement, be subjected to practically constant tension. In order to achieve a permanently tensioned condition also for the leno thread 37, the twoarmed lever 88 and the tension spring 89 are provided. The lever 8-8 is pivotal about the pivot 90 and carries on one arm an eyelet 91 through which the yarn 37 is guided. From the eylet 91, the thread travels to the pivotally mounted yarn bobbin 92. The yarn brake 97 is carried by the carrier 93 and serves to brake the yarn bobbin 92. The pivot 90 is secured, by means of the carrier 93, with the loom frame 98. The pivoting of the lever 88 is limited in one direction by the stop 94.

The drive mechanism or means shown in FIGURE 17 drives the arrangement shown in FIGURES 1 to 8. In operation, due to rotation of the pivot 81, the guide cams 82 to 85 are rotated in the direction of the arrow 95. Due to the rollers 78, 79 and 80 travelling along the guide cams, the levers 74 to 78 are caused to carryout pivoting movements about the pivot 96 and thereby to displace the healds 31, 32 and the yarn guides 36 and 46. It is quite clear for example from the shape of the guide cams that the shed-forming means comprised of elements 31, 32 and 46 associated with the guide cams 82, 83 and 85 carry out the same number 0f reciprocating movements and that yarn guide 46 always lags behind relatively to the movements of the yarn guide 36. In this way, there is no danger of the threads 33, 34 being engaged by the entrainment means of the yarn guide 46.

In order to make clear the path or configuration of the guide cam 84, which coincides in part with other cams, this cam has been given the reference numeral 84 at four different points.

Due to the movement of the leno thread 37, it would be alternatingly tensioned and again loosened, if the pivotal lever 88 were not provided. With each upward and downward movement of the eyelet 35 and with each entrainment movement of the thread 37 by the yarn guide 46, the variation in the required length of thread 37 is compensated by pivoting of the lever 88 which is subjected to the pull of the spring 89. The spring 89 is weaker than the yarn brake 97. As yarn is used up for the leno pattern, a replenishing supply of yarn thread is drawn in past the brake 97, as the lever 88 bears on the stop 94.

While the novel features of the invention have been shown and described and are pointed out in the claims, it is to be understood that various omissions, substitutions and changes in construction and arrangement of the the features shown and described may be made by those skilled in the art without department from the spirit and scope of the invention.

What is claimed is:

1. A method for the manufacture of a leno interlacing during a weaving operation, wherein a leno thread is wrapped around a predetermined number of warp threads, which comprises selectively guiding a leno thread in a reciprocatory` movement in a direction parallel to the direction of movement of the healds of a loom, both 0n one side of the predetermined number of warp threads and also on the other side of the predetermined number of warp threads; continuously retaining the leno thread on said one side; selectively retaining the leno thread on said other side in both end positions of the reciprocatory movement of the leno thread, and selectively inserting a weft thread through an open shed formed by the warp threads during the weaving operation when said leno thread is in an end position of said reciprocatory movements.

2. The method of claim 1, in which alternatingly, during one end position of the leno thread on said one side, the leno thread is reciprocated once on said other side and, during a second end position of the leno thread on said one side, the leno thread is reciprocated once on said other side, and between the two movements of each reciprocating movement, a weft thread is inserted on said other side.

3. The method of claim 1, in which the leno thread is reciprocated in phase opposition on both sides and is freed in a central zone of its movement on the said other side, said leno thread being, due to its movement on said one side guided about the warp thread and then reengaged on said other side and entrained into its end position, and during each end position of the crossing thread a weft thread is inserted.

4. The method of claim 2 in which before each movement of the leno thread into each of the end positions on said one side and after each movement of the leno thread into said end positions, a weft thread is inserted.

5. An arrangement for the manufacture of a leno interlacing having a leno thread wrapped about a predetermined number of warp threads, comprising a rst and a second thread guide means, each reciprocable in the direction of movement of the healds on a loom, for actuating a leno thread, the rst thread guide means disposed on one side of the predetermined number of warp threads and the second thread guide means disposed on the other side of the said predetermined number of warp threads; two entrainment means so arranged on said second thread guide means that during its reciprocating movement, one entrainment means entrains the leno thread in the one direction of movement and the other entrains the leno thread in the other direction of movement and an intermediate space between the two entrainment means in which the leno thread is freed from said entrainment means and which is open towards the predetermined number of warp threads.

6. The arrangement of claim 5 in which the first thread guide means is arranged externally of the shed and the second thread -guide means is arranged within the shed for the formation of a selvedge; said second thread guide means being shifted into the interior of the shed by the lount of threads equal to that of said predetermined mber of Warp threads.

7. The arrangement of claim 5 further comprising a .'ead guiding means, the leno thread extending from a 1o thread supply through the rst thread guide means, t said thread guiding means and the second thread guide 3ans to the leno interlacing, and the leno thread being ided by the thread guiding means at the end positions the first thread lguide means into the path of movement the entrainment means of the second thread guide sans.

8. The arrangement of claim 7, in which the thread riding means is formed with at least one slot comprising rectilinear portion extending parallel to the direction of ovement of the healds whereby the leno thread extendg through the rectilinear portion is kept outside the path movement of the entrainment means and also comprisg end portions so shaped and arranged relatively to the ith of movement of the entrainment means that a thread :tending through either of said end portions is disposed the path of movement of the entrainmenturneans.

9.' The arrangement of claim 8, in which both the leno lread and also the predetermined number of warp threads .'e guided through the slot; the shed movement of the arp threads by said healds moving the warp threads only ver the rectilinear portion of the slot or the commencelent of the shed movement of the said warp threads Aby lid healds being before the commencement of the movelent of the second thread guide means.

10. The arrangement of claim 8, in which the two en- 'ainment means provided b-y the second thread guide leans includes an elongated member formed at one longildinal side with a recess from which extend indentations lat are directed and are spaced apart in the longitudinal irection of said member, said indentations operating to ntrain the leno thread upon reciprocal movement in one r the other direction of said member.

v11. The arrangement of claim 10, in which two identical lots are provided by said thread guiding means, said slots eing in registry and the second thread guide means being aovable between the two slots parallel to the rectilinear ortions of the slots, the two entrainment means coinciding in the end positions, of their movements at least approximately with the ends of said slots.

12. The arrangement of claim 10, in which the spacing between the two indentations in the longitudinal direction of said member is at least equal to the spacing of the ends of the slot in the thread guiding means.

13. The arrangement of claim 5, in which the mutual arrangement of the two thread guide means is such that the leno thread extends from the leno thread supply through the rst thread guide means, emerges therefrom at a point which projects to the side towards the second thread guide means, travels from that point over the path of movement of the second thread guide means to the leno interlacing, and the lirst thread guide means has a wedgeshaped portion extending in'its longitudinal direction for deflecting the predetermined number of warp threads during its travel past said warp threads.

14. The arrangement of claim 5, further comprising a thread guiding means shaped as a rod which is arranged adjacent to the second thread guide means and parallel to the path of movement thereof, and which is so offset relatively thereto that the predetermined number of warp threads is guided out of the path of the second thread guide means.

References Cited UNITED STATES PATENTS 602,366 4/1898 Schumacher 139-54 X 922,357 5/ 1909 Tavella 139-54 X 2,547,170 4/1951 Picanol 139-54 3,227,191 1/1966 Julliard 139-383 FOREIGN PATENTS '1,494,816 8/1967 France.

557,087 8/1932 Germany.

10,552 1888 GrcarBriuuu.

160,469 11/1962 Russia.

JAMES KEE CHI, Primary Examiner U.S. C1.X.R. 139-383; 419 

